We're back on the subject of vegan desserts this week - and to be specific, vegan lemon meringue tart.

How can such a thing exist, without egg white, you may wonder?Well, that's certainly something I wondered. I had consigned meringue to the list of foods I had enjoyed and would enjoy no more if I were to remain committed to a plant-based diet in perpetuity. Yet here it was, amidst a fair field of cakes -some adorned with ruby-red strawberries, or luscious chocolate, spread like edible jewels on a table (literally like jewellery - one of the cakes was decorated with gold leaf), all created by gourmet cake makers Chouchoux (chouchoux.co.uk).

How, I asked, can that meringue be vegan?

It turns out you can use something called aquafaba. If that sounds like another expensive processed ingredient you would buy from a wholefood shop, think again. Remember that gunky water you might have tipped down the sink when you opened a tin of chickpeas in the unenlightened past? Well, aquafaba means water-bean and aquafaba is that gunky water, and you can use it as an egg white substitute.

Apparently this starchy liquid is a great binder that you can whip to create a foam. The science behind this is still under investigation but according to the aquafaba website (aquafaba.com), proteins and starches in the liquid tend to mimic the proteins in egg whites in many respects. It traps air, just as egg white does, so it has all sorts of useful culinary applications.

Three tablespoons of aquafaba approximates to one egg, depending on the consistency, which should be about the same as egg whites.

Beat chick pea juice with caster sugar to make meringues, but according to the Vegan Society, you can also use it to make mousse au chocolat, nougat and fudge, baked Alaska, strawberry ice cream, chocolate brownies, macarons, mayonnaise and more.

Its binding properties make it useful as when you need something to stick a savoury dish together - such as veggie burgers. Of course, the chick peas themselves are a good source of protein too.

But how does it taste?

My Chouchoux lemon meringue tart did not taste of chick peas. With a crisp, golden pastry case, a filling of smooth, tangy lemon, and the aquafaba soft meringue topping, it tasted divine.